README: document the new guest page controls

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -24,6 +24,12 @@ Opus 48 kHz stereo, 128 kb/s, in-band FEC. The guest page disables browser echo
 noise suppression and AGC. The "I'm wearing headphones" box is ticked by default; unticking it
 turns echo cancellation back on for guests on speakers.
 
+Guest page controls: **Mute my mic** (with a clear "the show cannot hear you" state),
+**Hear yourself** (own mic in their headphones; refused when the headphones box is unticked),
+and a **"What is happening"** panel. That panel logs connection events plus stats every 15 s
+in both directions, with no IP addresses. It stays in the guest's browser until they press
+Copy and send it to you (chat or email). Ask for it first when a guest sounds wrong.
+
 The receive side has an adaptive jitter buffer (v2, 2026-11-04): 80 ms start, max 300 ms.
 On an underrun it holds its place and refills to a larger target, so delayed packets are
 played rather than thrown away. It corrects guest/MOTU clock drift in both directions by